Study On The Resistance Of Pseudomonas Aeruginosa To Aminoglycoside Antibiotics And Its Related Resistance Genes

Objective: To investigate the relationship between aminoglycoside modifier and 16 SrRNA methylase and PA resistance by detecting the expression of aminoglycoside modifier genes and 16 SrRNA methylase of Pseudomonas aeruginosa(PA),which are not homologous to clinical isolation.To guide the clinical rationalization of drugs and antimicrobial research and development to provide basis and help.Methods:(1)The clinical specimens of the First Affiliated Hospital of Anhui Medical University from November 2013 to December 2015 were selected.After separation and pure culture,VETEC 2 COMPACT automatic microorganism analyzer and drug sensitivity test were used by Meiliai.The drug sensitivity judgment standard determines drug resistance,mediation,and sensitivity according to the critical values specified in the CLSI 2015 edition.The drug resistance of nine commonly used antimicrobial drugs in clinical practice is analyzed,and the strains of Pseudomonas aeruginosa resistant to amino glycosides are selected.(2)The aminoglycoside-modifying enzyme gene and the 16 SrRNA methylase gene were amplified by polymerase chain reaction,and sequenced and analyzed.the aminoglycoside modifying enzymes include aac(3)-I,aac(3)-II,aac(6’)-I,aac(6’)-II,ant(2’’)-I and ant(3).There are 6 kinds of ’’)-I,16 SrRNA methylase genotypes include armA,rmtA,rmtB,rmtC,rmtD,and the amplification products are analyzed by 2% agarose gel electrophoresis,which is equivalent to the positive control molecule.The results were considered to be positive results;the amplified products were purified and sequenced,and the sequencing results were compared with the rmtB sequences of the US nucleic acid library(GenBank)by Blast,and the modified enzyme homology was compared.RESULTS:(1)Sixty non-homologous Pseudomonas aeruginosa strains were isolated and identified.The drug sensitivity results showed that the highest resistance rate was cefpime(60.00 %).The drug resistance rate for Amiqiaxing,gentamycin,ceftazidine,imamipenan,ciprofloxacin,levofloxacin,tobumycin,piperacillin-tazobatam was 20 %-56.67 %.33 antiaminoglycoside antibiotic resistant Pseudomonas aeruginosa,27 antiaminoglycoside antibiotic intermediates and sensitive strains were selected.(2)Of the 33 strains of antiaminoglycoside antibiotic resistant Pseudomonas aeruginosa,28 strains detected aminoglycoside modizase genes with a detection rate of 84.85 %,including gene AAC(3)-II 15 strains,AAC(6 ’)-I9 strains,Aac(6 ’)-II 15 strains,ant(2’)-I24 strains,ant(3 ’)-I11 strains,no AAC(3)-I genotype detected,Gene detection rates were ant(2 ’)-I(32.43 %),AAC(3)-II(20.27 %),AAC(6’)-II(20.27 %),ant(3 ’)-I(14.86 %),AAC(6 ’)-I(12.16 %),the genotype with the highest detection rate in this study was ant(2’)-I,There are 2,3,10,9 and 4 strains of Pseudomonas aeruginosa that carry 5,4,3,2,and 1 aminoglycoside modifier genes at the same time,and 5 strains have not detected aminoglycoside modifier genes;No aminoglycoside modizase gene was detected in 27 strains of antiaminoglycoside antibiotics and sensitive strains.The drug-resistant Pseudomonas aeruginosa spectrum showed that 15 strains were multi-drug resistant(three or more types of antibiotic resistance),and 2 strains carried five drug-resistant genes at the same time.There are 24 strains of two or more aminoglycoside modifier genes.Accounting for 85.71 %.Of the 33 strains of copper-green pseudocell strains resistant to aminoglycosides,10 detected a 16 SrRNA methylase gene type rmtB,with a detection rate of 30.3 %;No 16 SrRNA methylase gene was detected in 27 antiaminoglycoside antibiotics and sensitive strains.The strain positive for the 16 SrRNA methylase rmtB gene showed a high level of resistance to gentamycin,the high value reached MIC & GT;512 mg/l,armA,rmtA,rmtC,rmtD genotype not detected.Conclusion: Pseudomonas aeruginosa has high resistance to aminoglycoside antibiotics,and bacteria carrying aminoglycoside modifier(AMEs)genes is one of the important factors that cause resistance of Pseudomonas aeruginosa in the region.Than carrying 16 SrRNA methylase rmtB gene is closely related to the high level of resistance to aminoglycoside antibiotics of Pseudomonas aeruginosa.